It is usually best to go to bed before 23:00 at night, and for normal adults, the best sleep time is 6-8 hours a day, and the deep sleep phase is greater than 4 hours as much as possible, and the deep sleep phase is spent at 2-3 a.m. Therefore, when you go to bed at 10-11 p.m., you can ensure that you are in the deep sleep phase within 2-3 a.m. In the deep sleep phase for the recovery of the cerebral cortex can get the best full rest and full regulation of plant nerve function, so sleep at 23:00 at night is the best rest and sleep time for the human body. If you sleep more than this time, even if the sleep time is greater than 6-8 hours, but because of the deep sleep phase is not enough for the body also has certain adverse effects.